<template>
    <div>
        <!-- 面包屑导航区 -->
        <el-breadcrumb separator-class="el-icon-arrow-right">
            <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
            <el-breadcrumb-item>商品管理</el-breadcrumb-item>
            <el-breadcrumb-item>添加商品</el-breadcrumb-item>
        </el-breadcrumb>

        <!-- 卡片视图 -->
        <el-card>
            <!-- 提示区域 -->
            <el-alert
                title="添加商品信息"
                type="warning"
                center
                show-icon
                :closable="false">
            </el-alert>
            <!--步骤条区域 -->
            <el-steps :space="200" :active="activeIndex - 0" finish-status="success" align-center>
                <el-step title="基本信息"></el-step>
                <el-step title="商品参数"></el-step>
                <el-step title="商品属性"></el-step>
                <el-step title="商品图片"></el-step>
                <el-step title="商品内容"></el-step>
                <el-step title="完成"></el-step>
            </el-steps>

            <!-- tab栏区域 -->
            <el-form 
                :model="addForm" 
                :rules="addFormRules" 
                ref="addFormRef" 
                label-width="100px"
                label-position="top"
            >
                <el-tabs 
                    v-model="activeIndex" 
                    :tab-position="'left'" 
                    :before-leave="beforeTabLeave" 
                    @tab-click="tabClicked"
                >
                    <el-tab-pane label="基本信息" name="0">
                        <el-form-item label="商品名称" prop="goods_name">
                            <el-input v-model="addForm.goods_name"></el-input>
                        </el-form-item>
                        <el-form-item label="商品价格" prop="goods_price">
                            <el-input v-model="addForm.goods_price" type="number"></el-input>
                        </el-form-item>
                        <el-form-item label="商品数量" prop="goods_number">
                            <el-input v-model="addForm.goods_number" type="number"></el-input>
                        </el-form-item>
                        <el-form-item label="商品重量" prop="goods_weight">
                            <el-input v-model="addForm.goods_weight" type="number"></el-input>
                        </el-form-item>
                        <el-form-item label="商品分类" prop="goods_cat">
                            <!-- 选择商品分类的级联选择框 -->
                            <el-cascader
                                v-model="addForm.goods_cat"
                                :options="catelist"
                                :props="cateProps"
                                @change="handleChange"
                                clearable
                                >
                            </el-cascader>
                        </el-form-item>
                    </el-tab-pane>
                    <el-tab-pane label="商品参数" name="1">
                        <!-- 渲染表单的item项 -->
                        <el-form-item :label="item.attr_name" v-for="item in manyTableData" :key="item.attr_id">
                            <!-- 复选框组 -->
                            <el-checkbox-group v-model="item.attr_vals">
                                <el-checkbox :label="cb" v-for="(cb, i) in item.attr_vals" :key="i" border></el-checkbox>
                            </el-checkbox-group>
                        </el-form-item>
                    </el-tab-pane>
                    <el-tab-pane label="商品属性" name="2">
                        <el-form-item :label="item.attr_name" v-for="item in onlyTableData" :key="item.attr_id">
                            <el-input v-model="item.attr_vals"></el-input>
                        </el-form-item>
                    </el-tab-pane>
                    <el-tab-pane label="商品图片" name="3">
                        <!-- action 表示图片要上传到的后台API地址 
                            on-preview 触发预览事件
                            on-remove 触发删除选中图片事件-->
                        <el-upload
                            :action="uploadURL"
                            :on-preview="handlePreview"
                            :on-remove="handleRemove"
                            list-type="picture"
                            :headers="headerObj"
                            :on-success="handleSuccess">
                            <el-button size="small" type="primary">点击上传</el-button>
                        </el-upload>
                    </el-tab-pane>
                    <el-tab-pane label="商品内容" name="4">
                        <!-- 富文本编辑器组件 -->
                        <quill-editor v-model="addForm.goods_introduce"></quill-editor>
                        <!-- 添加商品的按钮 -->
                        <el-button type="primary" class="btnAdd" @click="add">添加商品</el-button>
                    </el-tab-pane>
                </el-tabs>
            </el-form>
            <el-button type="primary" @click="goBack">回到商品列表页</el-button>
        </el-card>

        <!-- 图片预览 -->
        <el-dialog
            title="图片预览"
            :visible.sync="previewVisible"
            width="50%"
            >
            <img :src="previewPath" alt="" class="previewImg">
        </el-dialog>

    </div>
</template>

<script>
    import _ from 'lodash';

    export default {
        data(){
            return {
                activeIndex: '0',
                // 添加商品的表单数据对象
                addForm: {
                    goods_name: '',
                    goods_price: 0,
                    goods_number: 0,
                    goods_weight: 0,
                    // 商品所属的分类数组
                    goods_cat: [],
                    // 图片的数据
                    pics: [],
                    // 商品的详情描述
                    goods_introduce: '',
                    attrs: []
                },
                // 商品分类列表
                catelist: [],
                // 校验规则对象
                addFormRules: {
                    goods_name: [{
                        required: true,
                        message: '请输入有效商品名称',
                        trigger: 'blur'
                    }],
                    goods_price: [{
                        required: true,
                        message: '请输入商品价格',
                        trigger: 'blur'
                    }],
                    goods_number: [{
                        required: true,
                        message: '请输入商品数量',
                        trigger: 'blur'
                    }],
                    goods_weight: [{
                        required: true,
                        message: '请输入商品重量',
                        trigger: 'blur'
                    }],
                    goods_cat: [{
                        required: true,
                        message: '请输入商品分类',
                        trigger: 'blur'
                    }]
                    
                },
                // 级联选择框的配置对象
                cateProps: {
                    expandTrigger: 'hover',
                    // 具体选中值的属性
                    value: 'cat_id',
                    // 指定看到的属性
                    label: 'cat_name',
                    // 指定父子嵌套的属性
                    children: 'children',
                    // 是否严格的遵守父子节点不互相关联
                    checkStrictly: false
                },
                // 动态参数列表数据
                manyTableData: [],
                // 静态属性列表数据
                onlyTableData: [],
                // 上传图片的url地址
                uploadURL: 'http://127.0.0.1:8888/api/private/v1/upload',
                // 图片上传组件的headers请求头对象
                headerObj: {
                    Authorization: window.sessionStorage.getItem('token')
                },
                previewPath: '',
                previewVisible: false
            }
        },
        // 生命周期函数
        created(){
            this.getCateList();
        },
        methods: {
            // 获取所有商品分类数据
            async getCateList(){
                const {data: res} = await this.$http.get('categories');

                if(res.meta.status !== 200){
                    return this.$message.error('获取商品分类数据失败!');
                }
                this.catelist = res.data;
                console.log(this.catelist);
            },
            // 级联选择器选中项变化, 会触发这个函数
            handleChange(){
                console.log(this.addForm.goods_cat);
                if(this.addForm.goods_cat.length !== 3){
                    this.addForm.goods_cat = [];
                }
            },
            beforeTabLeave(activeName, oldActiveName){
                if(oldActiveName === '0' && this.addForm.goods_cat.length !== 3){
                    this.$message.error('请先选择商品分类!');
                    return false;
                }
            },
            async tabClicked(){
                // console.log(this.activeIndex);
                // 证明访问的是动态参数面板
                if(this.activeIndex === '1'){
                    const {data: res} = await this.$http.get(`categories/${this.cateId}/attributes`, 
                        {params: {sel: 'many'}});
                    if(res.meta.status !== 200){
                        return this.$message.error('获取动态参数列表失败!');
                    }
                    res.data.forEach(item => {
                        item.attr_vals = 
                        item.attr_vals.length === 0 ? [] : item.attr_vals.split(' ')
                    });
                    this.manyTableData = res.data;
                    console.log(this.manyTableData);
                } else if(this.activeIndex === '2'){
                    const {data: res} = await this.$http.get(`categories/${this.cateId}/attributes`,
                        {params: {sel: 'only'}});
                    if(res.meta.status !== 200){
                        return this.$message.error('获取静态属性列表失败!')
                    }
                    this.onlyTableData = res.data;
                    console.log(this.onlyTableData);
                }
            },
            // 处理图片预览效果
            handlePreview(file){
                console.log(file);
                this.previewPath = file.response.data.url;
                this.previewVisible = true;
            },
            // 处理移除图片的操作
            handleRemove(file){
                console.log(file);
                // 1. 获取将要删除的图片的临时路径
                const filePath = file.response.data.tmp_path;
                // 2. 从pics数组中, 找到这个图片对应的索引值
                const i = this.addForm.pics.findIndex(x => {
                    x.pic === filePath
                });
                // 3. 调用数组的splice方法, 把图片信息对象, 从pics数组中移除
                this.addForm.pics.splice(i, 1);
                console.log(this.addForm);
            },
            // 监听图片上传成功的事件
            handleSuccess(response){
                console.log(response);
                // 1. 拼接得到一个图片信息对象
                const picInfo = {pic: response.data.tmp_path};
                // 2. 将图片信息对象, push 到 pics 数组中
                this.addForm.pics.push(picInfo);
                console.log(this.addForm);
            },
            // 添加商品
            add(){
                this.$refs.addFormRef.validate(
                    async valid => {
                        if(!valid){
                            return this.$message
                                .error('请填写必要的表单项!')
                        }
                        // 执行添加的业务逻辑
                        // 需要深度拷贝, lodash cloneDeep(obj)
                        const form = _.cloneDeep(this.addForm)
                        form.goods_cat = 
                            form.goods_cat.join(',');
                        // 处理动态参数
                        this.manyTableData.forEach(item => {
                            const newInfo = {
                                attr_id: item.attr_id,
                                attr_value: item.attr_vals.join(' ')
                            };
                            this.addForm.attrs.push(newInfo);
                        });
                        // 处理静态属性
                        this.onlyTableData.forEach(item => {
                            const newInfo = {
                                attr_id: item.attr_id,
                                attr_value: item.attr_vals
                            };
                            this.addForm.attrs.push(newInfo);
                        });
                        form.attrs = this.addForm.attrs;
                        console.log(form);
                        // 发起请求添加商品
                        // 商品名称必须是唯一的
                        const { data: res } = await this.$http.post('goods', form);
                        
                        if(res.meta.status !== 201) return this.$message.error('添加商品失败!')
                        
                        this.$message.success('添加商品成功!');
                        this.$router.push('/goods');
                    }
                );
            },
            goBack(){
                this.$router.push('/goods');
            }
        },
        computed: {
            cateId(){
                if(this.addForm.goods_cat.length === 3){
                    return this.addForm.goods_cat[2];
                }
                return null;
            }
        }
    }
</script>

<style lang="less" scoped>
    .el-checkbox {
        margin: 0 10px 10px 0 !important
    }

    .previewImg {
       width: 100%; 
    }

    .btnAdd {
        margin-top: 15px;
    }
</style>